Abstract: A building construction system utilizing prefabricated stacked modules creating tubular resistant modules forming spaced hollow columns interconnected by bridges and a plurality of elongate structural profiles made of bendable steel used as column and beam components in the modules.

Abstract: A building element comprises a profile defined by a web, a pair of side flanges extending perpendicular to the web and outer corners joining the side flanges, respectively, to the web. The web includes a constriction extending in the same direction as the side flanges, planar segments disposed on opposite sides of the constriction, and inner corners joining the constriction to the planar segments. The constriction has a width that is about one-third the overall width of the building element. The constriction is bisected by a constriction axis perpendicular to the planar segments, and the constriction axis may be located along the height of the building element so as to be spaced from one of the side flanges a distance of or about one-third the overall height of the building element. The constriction forms an angle of or about 70°.

Abstract: A building element for use as a column or a beam includes a profile of substantially uniform cross-section extending lengthwise between first and second ends. The profile is defined by a web, a pair of side flanges perpendicular to the web, and curved outer corners joining the side flanges, respectively, to the web. The web includes at least one constriction extending in the same direction as the side flanges and having a pair of arms extending angularly inwardly toward one another from curved inner corners of the web to a curved base having an apex. The side flanges extend from the outer corners to tips, respectively, terminating at side edges, respectively. The building element has an overall width between the web and the tips. The at least one constriction has a width between the web and the apex about ⅓ the overall width.

Abstract: A building element for use as a column or a beam includes a profile of substantially uniform cross-section extending lengthwise between first and second ends. The profile is defined by a web, a pair of side flanges perpendicular to the web, and curved outer corners joining the side flanges, respectively, to the web. The web includes at least one constriction extending in the same direction as the side flanges and having a pair of arms extending angularly inwardly toward one another from curved inner corners of the web to a curved base having an apex. The side flanges extend from the outer corners to tips, respectively, terminating at side edges, respectively. The building element has an overall width between the web and the tips. The at least one constriction has a width between the web and the apex about ⅓ the overall width.